Electrochemically roughened nanoporous platinum electrodes for non-enzymatic glucose sensors

Abstract

A sensitive and reliable non-enzymatic electrochemical blood-glucose sensor has been fabricated using a nanoporous platinum sensing interface prepared by successive electrochemical formation and reduction of thick hydrous platinum oxide layers. The fabricated nanoporous platinum electrode exhibits sensitive amperometric responses to glucose in phosphate buffered saline (PBS) as well as ascorbic acid and uric acid. At an applied electrode potential of + 0.4 V (vs Ag|AgCl|satd. KCl) the oxidation current is non linear with glucose concentration following a Langmuir-like relation, with r2 = 0.994. The sensitivity over a linear range of 1 – 10 mM is (5.67 ± 0.18) µA cm-2 mM-1 with a detection limit of 0.8 mM. The lower limit of quantitation, at which the relative standard uncertainty is 10 %, is 2.3 mM. The sensor measured glucose concentration in human blood samples, showing good agreement with a commercial sensor. The results obtained make the proposed sensor a promising device for practical glucose monitoring in human blood